For other young people, Larsen advises they approach weight loss head on and not to wait until health problems begin setting in.
"I want to do it before I get into any health risks," she said.
The group's contestant with the most to lose is 33-year-old Bill Roberts, who said he hopes to lose more than 200 pounds, although he will let his body decide what he can handle.
Roberts is facing his second major attempt at weight loss. He first lost 80 pounds through the Weight Watchers program, but after severely breaking his arm, he had to take a break and the weight came back on.
"I want to get back on track as far as my weight loss," he said. "The second main reason [for joining the Biggest Loser] has to do with my nephew. He's in junior high now and I see him going down the same path I did at that age with weight and the lack of activity and improper eating habits."
As far as the first workout, Roberts said he was "excited."
"I have been in the gym setting before, but in this setting here, I have people who are in the same situation I am," explained Roberts. "I think we can have fun, I think we can push each other, and I'm looking forward to the relationships we're going to form here in this group."
For other people looking to lose weight, Roberts said the first step has to be taken by themselves.
"They can't be pushed into it," he said. "[It's] something they have to want to do deep down, and until they decide they want to do this for themselves, they're not going to have success."
The new group of contestants also brought in a mother-daughter duo who had conflicting thoughts about the first official workout.